This invention relates to a flavor delivery system, and in particular to a flavor delivery system which delivers flavor by means of an aerosol generated by mechanical dispersion of a liquid into a flowing gas stream.
Although smoking articles such as cigarettes have remained as popular consumer products, various new types of cigarette-type flavor delivery systems have been proposed. For example, as proposed in U.S. Pat. No. 4,079,742 to Rainer et al, tobacco substitutes can be provided from a wide variety of treated and untreated plant materials. However, it is believed that various types of tobacco substitutes, such as are provided by the modification of cellulose materials, are not completely satisfactory as a tobacco substitute.
Numerous aerosol generating smoking articles based on heat generation have been proposed. For example, U.S. Pat. No. 2,907,686 to Siegel proposes a cigarette substitute which includes an absorbent carbon fuel source and a flavoring agent. The flavoring agent is carried by the burnable fuel source and thereby provide hot gases. In addition, U.S. Pat. Nos. 3,258,015 and 3,356,094 to Ellis et al have proposed smoking articles whereby a fuel source of fine cut tobacco surround a tube containing a source of nicotine. Furthermore, substitute cigarette filler materials such as carbon fibers treated with flavorant are proposed in U.S. Pat. Nos. 3,738,374 to Bennett; 3,943,941 to Boyd; 4,044,777 to Boyd; 4,286,604 to Ehretsmann et al; 4,326,544 to Hardwick et al and British Patent No. 1,431,045. More recently, U.S. Pat. No. 4,340,072 to Bolt et al proposes a smoking article comprising a fuel rod having a central air passageway and a mouthend chamber containing an aerosol forming agent in the form of granular microcapsules. Another type of smoking article is disclosed in U.S. Pat. No. 3,515,417 to Moses.
A number of flavor delivery systems or simulated smoking devices which produce an aerosol or vapor without the application of heat also have been proposed. For example, wick-type devices are disclosed in U.S. Pat. Nos. 4,083,372 to Boden and 4,429,703 to Haber. Devices having pressurized substances are disclosed in U.S. Pat. No. 4,393,884 to Jacobs. A highly position sensitive aerosol generating device is disclosed in U.S. Pat. No. 2,764,154 to Murai. U.S. Pat. No. 2,445,476 to Folkman discloses a device having a tubular body of flexible material containing an air pervious filler saturated with a volatile oil, with plugs positioned at each end of the tube.
The aerosol generating smoking articles have not achieved any substantial commercial acceptance. The absence of such smoking articles from the marketplace is believed to be due to a variety of factors, including insufficient aerosol generation, poor taste, off taste due to the thermal degradation of the smoke forming agent and/or flavoring agents, the presence of substantial pyrolysis products and sidestream smoke, and unsightly appearance.
In addition, the heatless flavor delivery systems which have been proposed appear to be awkward to employ, provide inconsistent flavor generation, and often require use of absorbent materials and/or elaborate seals in order to prevent the flavor generating composition from escaping from the device prior to use.
In view of the deficiencies of the prior art, it would be highly desirable to provide a flavor delivery article essentially exhibiting the appearance of a conventional cigarette capable of delivering an aerosol without the application of heat.